Said to be super fast, lag free, and marked Android 2.2.1 i9000XXJPU, this could very well be the Froyo build you've always wanted for your Galaxy S. This build fixes many issues complained about in Froyo for Galaxy S, punching lag right in the face as well as a list of other items. Delivered by none other than the friendly folks over at XDA Developers Forum.

Take a peek at just some of the things this leak adds to your now-happy phone, courtesy of course of XDA superstar kalpik and friends:

Speed and sweetness. Remember that this is a leaked and non-official firmware update that cannot be installed through Kies. Some people who've upgraded have reported backup/restore to sdcard function missing. If you know what you're doing, feel free to upgrade. If you're unfamiliar with what to do with files that allow you to root and add an unofficial build upgrade to your phone, probably just don't do it.

Just updated to Froyo 2.2.1 thru Odin.. It works like a charm.. Fast, stable and so far everything is ok. I use Galaxy S.. Wil be testing for the next couple of days and repirt any bugs.

martti_s

I got my Galaxy S running the XXJPU upgrade through Odin. Works great. Kies refuses to recognize the phone.
I am not able to get a Samsung account.
The phone works beautifully, it is lightning fast and the little glitches that were still there in the 2.2. JP2 have been fixed.

With this firmware the Galaxy is the smartphone that I had been looking for.